1. Concise comparison of included trials.
| Study | Methodological quality | Duration/sample size | Disease duration | Peripheral arthritis | Baseline ESR | Intervention | Main results | Drop‐out |
| Clegg 1996 | Mutlicenter RCT Concealment: unclear risk Assessment: blind |
36 weeks/264 | 18.5+/‐11.6 | 29% | SSZ: 24.6+/‐18.0 Placebo: 25.2+/‐22.0 |
SSZ (or placebo) 2.0 g/d | ESR declined more with SSZ than with placebo (P < 0.0001). When comparing SSZ responders with non‐responders, the former had a greater decrease in ESR (P < 0.04) Patients with peripheral arthritis showed improvement that favored SSZ (P < 0.02) No significant difference in other parameters. One patient taking SSZ had severe adverse drug reaction |
19.3% |
| Corkill 1990 | RCT Concealment: unclear risk Assessment: blind |
48 weeks/62 | SSZ: 12.3+/‐8.2 Placebo: 16.1+/‐11.4 |
19% | SSZ: 15+/‐16 Placebo: 24+/‐26 |
SSZ (or placebo) 2.0 g/d | No significant difference between intervention groups | No data |
| Davis 1989 | RCT Concealment: unclear Risk assessment: blind |
3 months/30 | Median SSZ: 8.6 Placebo: 8.4 |
23% | SSZ: 24+/‐7.8(95% confidence limits) Placebo: 26.4+/‐8.6 |
SSZ (or placebo) 2.0 g/d | Claimed effective on the basis of before‐after comparison | 6.7% |
| Dougados 1986 | RCT Concealment: low risk Assessment: blind |
6 months/60 | Median 10 | 0% | SSZ: 13.5(median) Placebo: 11.0 |
SSZ (or placebo) 2.0 g/d | Success in patient assessment was more in SSZ than in placebo group. Function index and NSAIDs dosage were significantly improved in SSZ compared with placebo group. No difference was found in other parameters | 21.7% |
| Feltelius 1986 | RCT Concealment: unclear risk Assessment: blind |
12 weeks/37 | Median SSZ: 12.1 Placebo: 10.4 |
5% | SSZ: 24.3+/‐17.4 Placebo: 28.5+/‐19.5 |
SSZ (or placebo) up to 3.0 g/d | Only graphs (no figures) were presented. Compared with placebo group, morning stiffness and sleep disturbance were significantly improved in SSZ group Analysis of SSZ group showed that the greatest improvement were those with ESR > 20 mm/hr or haptoglobin > 3.8 g/L |
21.6% |
| Kirwan 1993 | RCT Concealment: low risk Assessment: blind |
3 years/89 | SSZ: 19+/‐12 Placebo: 21.9+/‐11.7 |
28% | No data | SSZ (or placebo) 2.0 g/d | Occurence of peripheral joint symptoms was lower in SSZ group: SSZ: 0.298 episodes/yr Placebo: 0.392 episodes/yr, P < 0.05 No difference was found in Schober test, chest expansion and cervical spine lateral flexion. More drop‐outs in SSZ group |
30.3% |
| Krajnc 1990 | RCT Concealment: unclear risk Assessment: blind |
24 weeks/95 SSZ = 71 Placebo = 24 |
No data | 66% | SSZ: 41+/‐19 Placebo: 43+/‐18 |
SSZ (or placebo) up to 3.0 g/d | On the basis of before‐after treatment comparison, duration of morning stiffness, number of painful and swollen joints, and ESR, there was significant improvement in SSZ group Duration of morning stiffness and ESR value were given in the paper and we found no significant difference between the intervention groups |
14.3% |
| Nissila 1988 | RCT Concealment: unclear risk Assessment: blind |
26 weeks/85 | SSZ: 5.4+/‐7.3 Placebo: 3.8+/‐4.3 |
68% | SSZ: 42+/‐20 Placebo: 46+/‐19 |
SSZ (or placebo) up to 3.0 g/d | Significant differences between intervention groups were observed in severity of morning stiffness, chest expansion and ESR. We also found severity of pain significantly improved in SSZ, compared with placebo group | 12.2% |
| Schmidt 2002 | RCT Concealment: unclear risk Assessment: blind? |
26 weeks/70 | SSZ: 16.7+/‐7.2 Placebo: 16.3+/‐7.8 |
36% | SSZ: 23.1+/‐3.2 Placebo 20.4+/‐2.4 |
SSZ (or placebo) 3.0 g/d | No significant difference was found between intervention groups except IgA. There were more drop‐outs in SSZ than in placebo group (18/34 versus 7/36) | 32.9% |
| Taylor 1991 | RCT Concealment: low risk Assessment: blind |
1 year/40 | SSZ: 11+/‐1.6 Placebo: 10.7+/‐1.6 |
15% | SSZ: 27 Placebo: 25 |
SSZ (or placebo) 2.0 g/d | No significant difference was found between intervention groups in all parameters except pain (measured with visual analogue scale). However, the pooled result showed no statistically significant, too | 17.5% |
| Winkler 1989 | RCT Concealment: unclear risk Assessment: blind? |
24 weeks/63 | Median SSZ: 10.8 Placebo: 11.2 |
33% | SSZ: 33.4+/‐20.4 Placebo: 26.9+/‐16.4 |
SSZ (or placebo) 2.0 g/d | The advantage of SSZ over placebo were significant only in the duration of morning stiffness and disturbance of sleep. The same results were found in the patients with axial form (N = 34). In patients with peripheral arthritis (N = 15), articular index showed significant improvement in SSZ over placebo | 22.2% |
ESR ‐ erythrocyte sedimentation rate g/d ‐ grams per day Ig A ‐ immunoglobulin A NSAIDs ‐ non‐steroidal anti‐inflammatory drugs RCT ‐ randomized controlled trials SSZ ‐ sulfasalazine